03/27/2014 at 12:00 PM EDT
This may be the tamest birthday party ever for legendary rocker Steven Tyler
, but the Aerosmith frontman still knows how to get the party going.
Tyler was honored in Washington D.C. on Tuesday at the National Music Publishers' Association Celebration of the American Songwriters
, where he accepted an award for his advocacy work on behalf of songwriters.
The rocker was also on Capitol Hill Monday to speak to members of Congress about protecting artists' rights to control how their songs are used.
"It's a bit like Mr. Smith goes to Washington," he joked. "Mr. Aerosmith in this case."
He was later fêted with a piano shaped cake which featured a caricature of his face in frosting for his 66th birthday.
"Steven was really surprised," says a source. "He was not expecting it."
Tyler wore a leather and metallic jacket, bell bottoms and a multitude of scarves and later took the stage to perform some of his classics, including his signature hit, "Walk This Way." Representative John Conyers, D-Mich, joined him onstage and Tyler showed him some of his rocker moves.
"Steven was teaching him how to walk this way," says a partygoer.
As for turning 66? "For Steven, age is just a number. He doesn't think about his age," says a friend.